If you are in Salt Water, you may want to reconsider this.
Salt begins to chrystallize at temps nearing 143*F.
If you are NOT in Salt Water, then you may want to increase the operating temperture some.
I can't answer your question re; the Herc KLC as to offering a thermostat location, but would find it odd if not.
If there is one, it will always be in a location where the cooling water will "leave" the engine.
(the thermostat's job is to hold back coolant, until temps dictate a release)
So follow the path from where the engine circulating pump supplies the engine block...., and learn where the cooling water leaves the engine.
If we cannot help you here, give
OldMarineEngine.com a try...... you may find some information there.
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